Emil elsaessee



Unwrap ."rarns EMIL ELSAESSER, OE ,BARMEN, PRUSSIA, GERMANY.

RED DYE-STUFF OR COLORING-MATTER.

SPECIFICATION forming part. of Letters Patent No. 329,634, dated November 3,1

Alllllicfllion filed J1me 1884. Serial No. 134,875, (Specimens) Patented in Germany March 2, 1884, No. 29,084, and in England May 14, 188 1, No. 7,713.

.To all whom it may concern/.-

Be it known that I, EMIL ELsAEssEmpf Barmen, in the Kingdom of Prussia andEiiipire of Germany, have invented certain new and useful Improvements in Dye-Stuffs or 001- oring-Matters, of which the following is aspecification.

This invention relates to red coloring-inatters or dye-stuffs which result from the action of the diazo compound of the hereinafter-described sulpho-acid of beta-naphthylamine upon alkaline solutions of sulpho-acids of alpha naphthol.

In preparing the sulpho-acid of beta-naphthylamiue, I mix one part of beta-naphthylamine with three parts of fuming sulphuric acid, and heat this mixture to a temperature ot'about? 5 ceutigrade. As soon as, by means of testing, it is shown to be soluble in alkaline solutions, as is the case after about an hour, this sulpho-acid is formed, which I then pour into water and separate the nearly-insoluble portions from the soluble parts in a manner well known to chemists. The mixture thus obtained contains three different sulpho acids,

from which I obtain my new sulpho-acidbt beta-naphthylamine in the followingmanner: I transform the sulpho-acids into their sodium salts and dry them carefully. The sodium salts are then boiled during an hour with six parts of alcohol of 93 to 96 Tralles, by which proceedings about sixty to seventy per cent. of the salts are dissolved. The alcoholic solution is then separated from the insoluble part by filtration, and the undissolved salt is obtained after having evaporated the alcohol. This salt contains the new snlphoacid, besides,.-v ery;

small quantities of another sulpho-acid. The salt thus obtained may immediately be used.

To obtain the acid quite pure, I dissolve the mixture of the salts extracted, by water, and precipitate the sulpho-acids by muriatic acid. I then transform the acids into their barium salts. Small quantities of a very diflicult-1y soluble barium salt precipitate. The principal part remains dissolved. This barium salt remaining dissolved contains the new sulpho-acid of beta-naphthylamine from which I obtain, in a manner well knowntb' chemists, its sodium salt.

In preparing the coloring-matters, I dissolve one part of the abovement-ionedsodmm salt of this monosulpho-acid of beta-naphthylamine. orof the atorementioned mixture of it, with small quantities of the other sulphoacid in twenty parts ot'cold water, and then add 1.5parts of muriatic acid ofthe specific gravity of 1.15, and after this twenty-two parts of fifteen-per-cent. solution of nitrate of sodium which is added according to well-known rules for preparing the diazo compound, which is termed, in chemical language, sulpho-acid ot beta-diazo-naphthylamine. This solutlon is mixed with another solution which is produced by mixing one part of the sodium salt of one of the monosulpho-acids ot'alpha-naphthol with 0.5 parts of caustic soda and thirty parts of water, care being taken to maintain the mixture at a temperature of about 6 to 8 centigrade. From this mixture the coloringmatter is then precipitated by common salt. The precipitate is compressed and then redissolved in boiling water, and finally dried.

The sulpho-acids ot'alpha-naphthol are prepared in a manner well known to chemists, and described by Nevile and \Vinther and Neve, by boiling the diazo compounds of monosulpho-acids of alphanaphthylamine with aeidnlated water.

The dye-stuff obtained by mixing the diazo compound of my new monosulpho-acid of beta'naphthylaminewith the monosulpho-acid of alpha-naphthol deri ed from the naphthionic acid dyes scarlet. That which is obtained with the monosulpho-acid of alpha-naphthol derived from the sulpho-naphthyladamic acid of Laurent dyes a reddish-blue shade.

The new dye-stuff exists as a reddish-brown powder, easily soluble in hot water. The water solution of the dye-stuff, if prepared as described from betanaphthylaminc, monosulpho-acid, and alpha-naphthol monosulphoacid, has a scarlet color. If made from alphanaphthol monosulpho-acid and sulpho-naphthyladamic acid, it has a bluish-red color. The addition of sulphuric acid to a Water solution of the new dye-stuff does not change the color of the solution. If, however, it be added to the dry powder, the latter dissolves, producing a red solution. The water solution of the new dyestuft, when boiled with zinc; dust, decolorizes, but changes after some time to a bluish color. If to this a sufficient quantity of hydrochloric acid is added, a precipitate forms consisting of the regenerated betanaphthylamine monosulpho-acid, which can be recognized by the following reactions: The free acid dissolves sparingly in cold or hot water, and is insoluble in alcohol. The dissolved part crystallizes from such solutions in needles or scales. The free acid is almost soluble in alcohol. The soda salt of this acid dissolves readily in ninety-fi ve (95) per cent.- of alcohol. When boiling, the water solution of this salt shows fluorescence of a reddishblue color. The lime or barium salts of this acid are easily soluble in water, but crystallize only from astron g1 y-concentrated solution. By means of nitrite of sodium or potassium the acid is easily converted into its diazo compound, which is a yellow color, and only dissolves in large quantities of water. If the solution of the reduced dye-stuff is boiled with nitric acid, it assumes a yellow color. The

chemical constitution of the new dye-stuff above described may be expressed by the following formula:

N aSOfi H N; NG H sO Na If) OH(d) I do not here claim the new sulpho-acid above referred to, but

monosulpho-acid of beta-naphthylamine, and

the IllOllOSlllpllO-flGldS of alpha-naphthol derived from naphthionic acid andsulpho-naphthyladamic acid, an dhaving the characteristics and qualities herein described.

In testimony whereof I have signed my name to this specification in the presence ot'two subscribing witnesses.

EMIL ELSAESSER.

\Vitnesses:

A. DAUL, F. GAESS. 

